Commentary on why implementing and standardizing histologic diagnosis of myocarditis is crucial for the clinical setting and patient care.

• Histological examination of endomyocardial biopsy or myocardium at autopsy is key to the diagnosis of myocarditis. • There is currently extensive variability in criteria used by pathologists to diagnose myocarditis. • It is difficult to achieve a consensus diagnosis of myocarditis, even amongst experienced cardiovascular pathologists. Histological examination of endomyocardial biopsy or myocardium at autopsy is key to the diagnosis of myocarditis. Among pathologists there is currently extensive variability in routine practice and criteria used to define, diagnose, and report myocarditis as well as to achieve consensus on cases. Two manuscripts emphasizing the need to standardize and implement histopathological diagnostic criteria for myocarditis are reviewed. [ABSTRACT FROM AUTHOR]